Prior art devices have been invented which teach Braille letters, words, and sentence structure to the visually impaired. U.S. Pat. No. 4,880,384 by the inventor of the present invention shows one such device which is a predecessor to the present invention. The inventor's prior Patent discloses building blocks having raised dots representing Braille characters which can be arranged on a board to create words or sentences. The prior art apparatus, while useful for teaching the visually impaired, has many deficiencies.
In the prior art, the shape of the Braille blocks having four sides and four corners allows for the blocks to be placed in more than one orientation on the board. The blocks in the prior art do not provide a way for the visually impaired to properly orient blocks on the board.
Second, the shape of the board on which the blocks are placed also does not provide for orientation of the board. It is essential that a visually impaired person can properly orient the board to read the word or sentence formed by the Braille blocks.
Third, the Braille teaching apparatus shown in the prior art does not provide for a way to space the blocks for easy alignment to form words or sentences. The Braille blocks are attached to protrusions on the board. The protrusions form a regular pattern on the board, and the blocks can easily be misaligned when placed together to form words or sentences.
Fourth, the Braille blocks in the prior art apparatus do not provide for visual indication to allow communication with non-visually impaired, i.e. parents, brothers, sisters, etc. In using the prior art apparatus, the non-visually impaired who do not know how to read Braille would not be able to read the words or sentences formed with the Braille blocks.
Fifth, the prior art apparatus also provides for use only in teaching Braille letters, words and sentence structure. The prior art does not provide for a way to use the apparatus to communicate in other contexts such as a message board or a refrigerator board.
Additionally, the prior art block patterns of raised protrusions are difficult to tactilly discriminate given their flat top surface. Accordingly, what is needed is the modified symbolic language teaching and communication system of the present invention. The shape of the blocks is modified to allow for easy orientation on a block engaging slate which also has a modified shape for orientation. The blocks are also provided with indicia so that they may be read by someone who is not visually impaired and include protrusions with rounded top portions. Further, in addition to being used as a Braille teaching apparatus, the slate can be mounted to different surfaces to communicate messages to others in any symbolic language using tactile pattern discrimination.